A "Crossover Event" refers to a situation where characters, storylines, or elements from different fictional universes or franchises interact with each other. This can occur in various media, including television shows, movies, comic books, and video games. For example, a crossover might feature characters from Marvel and DC Comics appearing together in a single storyline. These events are often designed to attract fans from both franchises and create unique storytelling opportunities. They can lead to exciting collaborations, such as a special episode of a TV series where characters from different shows meet, or a comic book series that combines heroes from multiple universes.